[Expression of cyclin D1 in brain gliomas and its significance]

Abstract

Background & objective: Overexpression of cyclin D1 was shown in many tumors. The excessive expression of cyclin D1 is an important cause of many tumors. But there are still some controversies of whether the overexpression of cyclin D1 exists in brain gliomas. This study was to determine the expression level of cyclin D1 in glioma tissues of human brain, and to analyze the relationship of cyclin D1 with the malignancy and prognosis of gliomas.

Methods: The expression levels of cyclin D1 in 84 specimens were determined by SP immunohistochemical assay. The correlation of expression intensity of cyclin D1, positive cell ratio of glioma tissues with the tumors malignancy, and the prognosis of the patients was analyzed.

Results: (1) The average percentages of cyclin D1 positive cells were (9.82+/-9.75)% and (27.45+/-21.03)% in the low grade gliomas and the high grade gliomas, respectively. There was significant difference between two groups (P< 0.01). (2) The cyclin D1 positive ratios were 31.25% (10/32) and 61.53% (32/52) in the low grade gliomas and the high grade gliomas, respectively. There was significant difference between two groups (P< 0.01). (3) The cyclin D1 positive ratios were 76.19% (16/21) and 24.00% (6/25) in recurrence group and non-recurrence group,respectively. There was significant difference between two groups (P< 0.01). (4) The cyclin D1 positive ratios were 66.67% (14/21) and 32.00%(8/25) in dead group and survival group, respectively. There was significant difference between two groups (P< 0.05). In dead group, the cyclin D1 positive ratios were 86.66%(13/15) and 16.66%(1/6) in the high grade gliomas and the low grade gliomas, respectively. There was significant difference between two groups (P< 0.05).

Conclusions: (1) The expression of cyclin D1 increased with the increased grade of glioma. (2) The higher cyclin D1 expressed, the worse prognosis the patients had. (3) The expression of cyclin D1 can act as a biological marker in evaluating malignancy of gliomas and prognosis of patients.